// 函数
function foo(x:string,y:number):string{
    return x+y
}
foo('qwww',1477);

let fun=function(x:string,y:number):string{
return x+y
}
console.log(fun('eee',444))


// ts完整的写法
let boo:(x:string,y:number)=>string=function(x:string,y:number):string{
    return x+y
};
console.log(boo('sdsd',231))
// 形参默认值
function bool(x:string,y:string,z?:string):string{
    return x+y+z
}
console.log(bool('a','b',))

interface Fun{
    (x:string,y:string):string
}
let yangyang:Fun=function(x:string,y:string):string{
    return x+y
}
console.log(yangyang('a',"b"))















export{
    foo

}